Kids who are better at resisting unhelpful impulses and distractions go on later in life to perform better academically, professionally and socially. But how this kind of self-control develops with age has not been so clear. Teenagers’ show more self-control than children in many ways, but in other respects – think of their propensity for risk-taking – they actually seem to show less.

In a new paper, published in Developmental Science, Ania Aïte at Paris Descartes University, France, led research investigating whether this might be because there are two types of impulse control – “cool” control, in which emotions are not involved, and “hot” control, in which they are – and that they might show different developmental trajectories. If so, this could have implications for educational interventions aimed at reducing teens’ sometimes dangerous behaviour.

The team studied 56 children (aged about 10), 48 adolescents (aged around 13), and 56 young adults (aged about 21). They all completed two different tests of their inhibitory control. In the emotionally neutral test, a classic version of the famous Stroop task, the participants had to indicate, as quickly but accurately as possible, the ink colour of a colour-denoting word (the word “red” written in blue, for example). It requires inhibitory control to ignore word meaning when there’s a mismatch between the word and its ink colour.

In a test of “hot” inhibitory control, the participants saw a series of faces displaying either happiness, anger, fear and sadness, each with either a congruent or incongruent emotional word written below. The participants had to indicate the emotion shown on each face, ignoring the word below.

On the emotionally neutral task, the adults did better than the adolescents, who did better than the younger children – there was linear improvement with age, just as you might expect. But the results for the emotion test were very different. Adults did better than the younger children, but the adolescents performed the worst.

It’s not that the adolescents were worse at identifying emotions – because when the facial expressions and emotion words matched, there was no difference between their performance and that of the adults. Rather, when there was a face-word mismatch, they found it harder to ignore the emotion word, and to focus only on the facial expressions.

The findings appear consistent with the popular idea that adolescence represents a time of heightened sensitivity to emotional stimuli, combined with immature connections between the pre-frontal cortex and emotional brain regions, making it more difficult for them to over-rule inappropriate impulses.

If adolescence is associated specifically with poor emotional control, but mature “cool” inhibitory control, this might explain why teens can typically cope fine with exams and other situations that demand “cool control”, yet find it harder than adults to ignore emotional influences, such as friends cheering them on to drink more alcohol, for example. This could explain their characteristically poor decision-making – such as driving while drunk and getting into fights.

“With poor decision-making being responsible for a rise in mortality during adolescence,” the researchers write, “the present findings could usefully contribute to the development of adolescent’ educational programs centered on hot inhibitory control.”